Shoulder strap



FIG. 1 is a top view of the shoulder strap, it being understood that the straps, buckles, zipper assembly and valve shown in broken lines are for illustrative purposes only and form no part of the claimed design and that the dashed lines around the perimeter of the shoulder strap represent stitching.

FIG. 2 is a bottom view thereof;

FIG. 3 is a left side view thereof, the right side view being a mirror image of the left side view;

FIG. 4 is a front view thereof; and,

FIG. 5 is a rear view thereof. 

The ornamental design for a shoulder strap, as shown and described. 